Determination of lutetium by fluorimetry, using BPMPHD and CTMAB

Lutetium(III) forms an association compound with a new synthetic reagent, 1,6-bi(1-phenyl-3-methyl-5-pyrazolone-4)hexandione (BPMPHD), and cetyltrimethylammonium bromide (CTMAB). The compound enhances the natural fluorescence of BPMPHD remarkably, upon which a new fluorescence method was developed for determining lutetium in rare earth (RE) samples. The determination range was 1.80 × 10^–7–8.8 × 10^–6 g/ml. The determination limit was 29 ng/ml. The composition of the ion associate was [Lu(BPMPHD)₂]–CTMAB⁺.     

Synthesis and Insulin—sensitizing Activity of a Series of 2—Benzyl—1,3—dicarbonyl Derivatives

A series of 2-benzyl-1,3-dicabonyl derivatives was synthesized.Their insulin-sensitizing activity was evaluated in 3T3-L1 preadipocyte cells.Compounds3,26 and 27 were found to possess strong insulin-sensitizing activity in vitro and were selected for further hypoglycemic evaluation in vivo.     

钴膦簇合物的催化环丙烷化反应

本文首次利用碳基钴簇合物ＰｈＰＣｏ_３（ＣＯ）_９催化剂，在常压和－２０℃－０℃，用苯乙烯和重氮乙酸乙酯进行环丙烷化反应，合成了菊酸酯，重氮乙酸乙酯可全部转化，酯的选择性可达８５％。产物经减压分馏后，由ＩＲ和￣１ＨＮＭＲ分析，确证了产物为菊酸酯，表明了羰基钴簇合物对苯乙烯的环丙烷化反应有良好的催化性能，为四面体异核簇合物用于不对称催化反应打下了基础。     

尼龙1010／尼龙6共聚物的表观相图研究

采用显微熔点法和ＤＳＣ测定了尼龙１０１０／尼龙６共聚物的表观相图；分析了投料比与链节结构单元含量的关系。最低熔点时尼龙１０１０／尼龙６的理论重量投料比为６０／４０，摩尔比为３３．３／６６．７，实验结果与此相近。     

Direct Trimethylsilylation of Phenanthrene and its Products—An Abnormal Silylation of Phenanthrene

Direct trimethylsilylation¹⁾ of phenanthrene in different molar ratio of phenanthrene/sodium/trimethylchlorosilane is reported and discussed. Instead of the aromatic silyl compounds, such as 9-trimethylsilylphenanthrene (V), the hydroaromatic silyl compounds, such as 9, 10–bis (trimethylsilyl)-9, 10-dihydrophenanthrene (I) were obtained preferentially. Structure of these compounds are characterized and discussed. These silylated products have a general trend to change their properties during long time storage in the atmosphere under exposure to light. A significant difference of chemical shifts between silylated aromatic compound (V) and silylated hydroaromatic compound (I-IV) was observed.     

Novel metathesis catalysts based on ruthenium 1,3-dimesityl-3,4,5,6-tetrahydropyrimidin-2-ylidenes: synthesis, structure, immobilization, and catalytic activity

The synthesis of novel ruthenium-based metathesis catalysts containing the saturated 1,3-bis(2,4,6-trimethylphenyl)-3,4,5,6-tetrahydropyrimidin-2-ylidene ligand, that is, [RuCl2(NHC)[=CH-2-(2-PrO)-5-NO(2)-C6H3]] (1) and [Ru(CF3COO)2(NHC)[=CH-2-(2-PrO)-5-NO2-C6H3]] (2) (NHC=1,3-bis(2,4,6-trimethylphenyl)-3,4,5,6-tetrahydropyrimidin-2-ylidene) is described. Both catalysts are highly active in ring-closing metathesis (RCM) and ring-opening cross-metathesis (ROCM). Compound 1 shows moderate activity in enyne metathesis. Compound 2 is not applicable to enyne metathesis since it shows high activity in the cyclopolymerization of diethyl dipropargylmalonate (DEDPM). Poly(DEDPM) prepared by the action of 2 consists of 95% five-membered rings, that is, poly(cyclopent-1-enevinylene)s, and 5 % of six-membered rings, that is, poly(cyclohex-1-ene-3-methylidene)s. The polymerization proceeds in a nonliving manner and results in polyenes with broad polydispersities (1.9< or =PDI< or =2.3). Supported analogues of 2 were prepared by immobilization on hydroxymethyl-Merrifield resin and a monolithic support derived from ring-opening-metathesis polymerization (ROMP). Catalyst loadings of 1 and 2.5%, respectively, were obtained. Both supported versions of 2 showed excellent reactivity. With 0.24-2% of the supported catalysts, yields in RCM and ROCM were in the range of 76-100%. Leaching of ruthenium was low and resulted in Ru contaminations of the products of less than 0.000014% (0.14 ppm).     

Crystal engineering of a versatile building block toward the design of novel inorganic-organic coordination architectures

Six novel inorganic-organic coordination supramolecular networks based on a versatile linking unit 4-pyridylthioacetate (pyta) and inorganic Co(II), Cu(II), Ag(I), Zn(II), Mn(II) and Pb(II) salts have been prepared in water medium and structurally characterized by single-crystal X-ray diffraction analysis. Reaction of CoCl(2).6H(2)O with Hpyta afforded a neutral mononuclear complex [Co(pyta)(2)(H(2)O)(4)](1), which exhibits a two-dimensional (2-D) layered architecture through intermolecular O-HO interactions. Reaction of CuCl(2.2H(2)O with Hpyta yielded a neutral one-dimensional (1-D) coordination polymer [[Cu(pyta)(2)(H(2)O].0.5H(2)O](n)(2) consisting of rectangle molecular square units, which show a three-dimensional (3-D) supramolecular network through S...S and O-H...O weak interactions. However, when AgNO(3), Zn(OAc)(2).2H(2)O or MnCl(2).4H(2)O salts were used in the above self-assembled processes, the neutral 2-D coordination polymers [Ag(pyta)](n)(3), [[Zn(pyta)(2)].4H(2)O](n)(4) or [[Mn(pyta)(2)(H(2)O)]](n)(5) with different topologies were obtained, respectively. While substituting the transition metal ions used in 1-5 with Pb(OAc)(2).3H(2)O, a one-dimensional coordination polymer [Pb(pyta)(2)](n)(6), which shows a novel 2-fold interpenetrating 2-D supramolecular architecture through weak SS interactions, was isolated. It is interesting to note that the building block pyta anion exhibits different configurations and coordination modes in the solid structures of complexes 1-6. These results indicate that the versatile nature of this flexible ligand, together with the coordination preferences of the metal centers, play a critical role in construction of these novel coordination polymers or supramolecules. The spectral and thermal properties of these new materials have also been investigated.     

烟酸对酸性硫酸盐体系铜电沉积的影响

对溶液A: 0.8 mol•L－1硫酸铜,0.6 mol•L－1硫酸,5.0×10－5 mol•L－1氯离子,1.0×10－4 mol•L－1聚乙二醇的溶液,溶液B:在溶液A中加入2.0×10－2 mol•L－1烟酸,pH为0.5,运用循环伏安和计时安培法研究玻碳电极上铜的电沉积行为.结果表明,铜的电沉积过程经历了晶核形成过程,其电结晶按瞬时成核和三维生长方式进行.烟酸的加入对铜的电沉积具有阻化作用,但不改变铜的电结晶机理.沉积层的X射线衍射表明Cu为面心立方结构,在烟酸存在下沉积层出现(220)高择优取向,这可能是烟酸在Cu(220)晶面上发生强烈吸附作用的结果.     

甲烷二氧化碳介质阻挡放电转化产物分布研究

针对介质阻挡放电甲烷二氧化碳转化实验,分析了反应的产物分布,探讨了进料组成和反应器结构对反应的影响.反应产物包括:高H2/CO摩尔比的合成气、气态烃、高辛烷值的汽油组分、醇和酸等含氧有机物.对所述电极结构,产物的选择性随碳数增加而降低;高的甲烷进料浓度有利于烃的生成,对醇和酸的最佳甲烷进料体积分数范围在67.4％～75.1％;放电间隙越小,原料转化率和烃、酸的选择性越大,大的放电间隙对醇的生成有利.